Introduction to the potential of Ferula ovina in dental implant research due to estrogenic bioactive compounds and adhesive properties.

Recent developments in dental implant have heightened the urgent need to natural tissue adhesives estrogenic materials with ability of promoting the proliferation and osteoblastic differentiation in human dental pulp-derived stem cells, to provide better integration of tissue for dentistry. Up to now, far little attention has been paid to adhesives extract of the root of Ferula sp. which contains biomaterial compounds with estrogenic activities. Prior to undertaking the investigation, analysis of the extract of the root of F. ovina revealed a novel terpenoid, and we identified it as Fenoferin. So far, this paper has focused on Fenoferin compared to Ferutinin and root extract to determine if Fenoferin caused changes in craniofacial cartilage, bone (ceratohyal) and tooth mineralization. Following the purpose of study, we used zebrafish as a well-developed model system for studying bone development, so the developing zebrafish larvae were exposed to various concentration of compounds at 2dpf, and the histological analyses were performed at 6dpf. The result of the current study highlights the importance of F. ovina in studies related to dental regenerative medicine.

Studying the Expression Efficiencies of Human Clotting Factor IX Analogs, Rationally-designed for Hyper-glycosylation.

Glyco-engineering has attracted lots of interest in studies dealing with the pharmacokinetics of therapeutic proteins. Based on our previous in-silico studies, two sites were selected in the N-terminal gamma-carboxy glutamic acid-rich (Gla) domain of the human clotting factor IX (hFIX) to add new N-glycosylation sites. Site-directed mutagenesis was employed to conduct K22N and R37N substitutions and introduce new N-glycosylation sites in the mature hFIX. The expression efficiencies of the mutants, in parallel with the wild-type hFIX (hFIXwt), were assessed in suspension adapted Chinese hamster ovary (CHO-s) cells at transcriptional, translational, and post-translational levels. The transcription levels of both N-glycosylation mutants were significantly lower than that of the hFIXwt. In contrast, at the protein level, the two hFIX mutants showed higher expression. The occurrence of hyper-glycosylation was only confirmed in the case of the hFIXR37N mutant, which decreased the clotting activity. The higher expression of the hFIX mutants at protein level was evidenced, which could be attributed to higher protein stability, via omitting certain protease cleavage sites. The coagulation activity decline in the hyper-glycosylated hFIXR37N mutant is probably due to the interference of the new N-glycan with protein-protein interactions in the coagulation cascade.

A pH-sensitive delivery system based on N-succinyl chitosan-ZnO nanoparticles for improving antibacterial and anticancer activities of curcumin.

Inherent selective cytotoxicity, antibacterial activity and unique physicochemical properties of ZnO nanostructures and chitosan (CS) make them promising candidates for drug delivery. In this study, ZnO nanoparticles functionalized by N-succinyl chitosan as a pH-sensitive delivery system were synthesized to enhance the therapeutic potential of curcumin (CUR). CS coated-ZnO nanoparticles were synthesized by a co-precipitation method in the presence of CS. Chemical modification of CS-ZnO particles was performed by succinic anhydride for introducing -COOH functional groups which were then activated using 1,1'­carbonyldiimidazole for CUR conjugation. The spherical-like CUR-conjugated system (CUR-CS-ZnO) with the average particle size of 40 nm presented significantly enhanced water dispersibility versus free CUR. The experimental study of CUR release from the system showed a pH-sensitive release profile, which enabled drug delivery to tumors and infection sites. MTT and Annexin-V FITC/PI assays revealed the superior anticancer activity of CUR-CS-ZnO compared to free CUR against breast cancer cells (MDA-MB-231) by inducing the apoptotic response with no cytotoxic effects on HEK293 normal cells. Moreover, CUR conjugation to the system notably dropped the MIC (25 to 50-fold) and MBC values (10 to 40-fold) against S. aureus and E. coli. The features qualify the formulation for anticancer and antimicrobial applications in the future.

Flower-like curcumin-loaded folic acid-conjugated ZnO-MPA- ßcyclodextrin nanostructures enhanced anticancer activity and cellular uptake of curcumin in breast cancer cells.

Non-spherical structures are beneficial to advance drug delivery effectiveness compared with common spherical ones, due to increased drug loading capability, improved bonding to a vascular wall, enhanced cellular uptake efficacy and prolonged circulation times. In this study, flower-like Zinc oxide-ßcyclodextrin (ßCD) nanostructures functionalized by 3-mercaptopropionic acid (MPA) as a non-spherical delivery system was successfully synthesized for aqueous delivery of curcumin (CUR) to enhance its targeting, bioavailability, and release profile. Terminal carboxyl functional groups were used for the conjugation of folic acid (FA) with the aim of active targeting to folate overexpressing breast cancer cells. The in vitro experimental study and mathematical modeling of CUR release revealed a sustained release with Fickian diffusion as the major release mechanism. MTT, colony formation and Annexin-V FITC/PI assays showed the superior anticancer effect of the system compared to free CUR against breast cancer cell line MDA-MB-231 by promoting the apoptotic respond with no cytotoxic effect on HEK293 normal cells. The efficacy of targeting strategy with FA moieties was demonstrated using the augmented cellular uptake of the FA-conjugated system on overexpressed folate receptor alpha (FRα) cells (MDA-MB-468 breast cancer cell line). Furthermore, loading of CUR to the delivery systems significantly lowered the MIC values (2.5 to 5-fold) against S. aureus and E. coli the infections of which are serious problems in cancer patients. According to the results of this study, the system can serve as a promising non-spherical delivery vehicle for enhancing bioavailability and targeting of hydrophobic anticancer agents in the future.

Impact of Prolonged Fraction Delivery Time Modelling Stereotactic Body Radiation Therapy with High Dose Hypofractionation on the Killing of Cultured ACHN Renal Cell Carcinoma Cell Line.

INTRODUCTION: Stereotactic body radiotherapy delivers hypofractionated irradiation with high dose per fraction through complex treatment techniques. The increased complexity leads to longer dose delivery times for each fraction. The purpose of this study is to investigate the impact of prolonged fraction delivery time with high-dose hypofractionation on the killing of cultured ACHN cells. METHODS AND MATERIALS: The radiobiological characteristics and repair half-time of human ACHN renal cell carcinoma cell line were studied with clonogenic assays. A total dose of 20 Gy was administered in 1, 2 or 3 fractions over 15, 30 or 45 min to investigate the biological effectiveness of radiation delivery time and hypofractionation. Cell cycle and apoptosis analysis was performed after 3-fraction irradiation over 30 and 45 min. RESULTS: The α/ß and repair half-time were 5.2 Gy and 19 min, respectively. The surviving fractions increased with increase in the fraction delivery time and decreased more pronouncedly with increase in the fraction number over a treatment period of 30 to 45 min. With increase in the total radiation time to 30 and 45 min, it was found that with the same total dose, 2- and 3-fraction irradiation led to more cell killing than 1-fraction irradiation. 3-fraction radiation induced G2/M arrest, and the percentage of apoptotic cells decreased when the fraction delivery time increased from 30 min to 45 min. CONCLUSION: Our findings revealed that sublethal damage repair and redistribution of the cell cycle were predominant factors affecting cell response in the prolonged and hypofractionated irradiation regimes, respectively.

Identification of methionine oxidation in human recombinant erythropoietin by mass spectrometry: Comparative isoform distribution and biological activity analysis.

BACKGROUND: Oxidative degradation of human recombinant erythropoietin (hrEPO) may occur in manufacturing process or therapeutic applications. This unfavorable alteration may render EPO inefficient or inactive. We investigated the effect of methionine/54 oxidative changes on the amino acid sequences, glycoform distribution and biological activity of hrEPO. METHODS: Mass spectrometry was applied to verify the sequence and determine the methionine oxidation level of hrEPO. Isoform distribution was studied by capillary zone electrophoresis method. In vivo normocythemic mice assay was used to assess the biological activity of three different batches (A, B, and C) of the proteins. RESULTS: Nano-LC/ESI/MS/MS data analyses confirmed the amino acid sequences of all samples. The calculated area percent of three isoforms (2-4 of the 8 obtained isoforms) were decreased in samples of C, B, and A with 27.3, 16.7, and 6.8% of oxidation, respectively. Specific activities were estimated as 53671.54, 95826.47, and 112994.93 mg/mL for the samples of A, B, and C, respectively. CONCLUSION: The observed decrease in hrEPO biological activity, caused by increasing methionine oxidation levels, was rather independent of its amino acid structure and mainly associated with the higher contents of acidic isoforms.

Functionalization of ZnO nanoparticles by 3-mercaptopropionic acid for aqueous curcumin delivery: Synthesis, characterization, and anticancer assessment.

Inherent biocompatibility and stability of zinc oxide nanoparticles (ZnO-NPs) and their biomedical potentials make them an emerging candidate for drug delivery. The aim of this study was to develop and assess a simple procedure for surface functionalization of ZnO-NPs by 3-mercaptopropionic acid (MPA) for water-soluble curcumin delivery. Carboxyl-terminated ZnO nanoparticles were successfully made using ZnCl2 and NaOH in the presence of MPA. The functional groups were activated by 1,1'-carbonyldiimidazole (CDI) and the curcumin bonding was carried out at room temperature for 24h. The core-shell nanocomposite had a significant better solubility versus free curcumin, as characterized by XRD, FTIR, UV-Vis spectrophotometry, DLS, and TEM, p<0.005. In addition, MTT cytotoxicity assessment on MDA-MB-231 breast cancer cells revealed a drop of IC50 values from 5µg/mL to 3.3µg/mL for free curcumin and ZnO-MPA-curcumin complex, respectively. This result showed an augmented cancer-inhibitory effect of nanoconjugate complex. In conclusion, the presented improved solubility and elevated functionality of novel ZnO-MPA-curcumin nanoformula is promising, and could be considered for new therapeutic endeavors.

Molecular Design, Expression and Evaluation of PASylated Human Recombinant Erythropoietin with Enhanced Functional Properties.

Erythropoietin (EPO) is the principal hormone which, has somewhat short half-life involved in the differentiation and regulation of circulating red blood cells. The present study was carried out to evaluate the capability of a polyethylene glycol mimetic technology as a biological alternative to improve pharmaceutical properties of human recombinant EPO. In silico models of EPO fused to 200 amino acids of proline, alanine, and serine (PAS) were initially generated and assessed by molecular dynamic (MD) simulation. The fluctuations of the modeled structure reached a plateau after 6000 ps of MD simulation. The Phi and psi analysis showed >99.2% of residues were located in the allowed regions. An expression vector consisting of EPO cDNA tagged to PAS coding sequences was synthesized and expressed in CHO-K1 Cells. The produced PASylated molecule was purified and characterized by standard analytical methods. The molecular weight of fusion protein was expanded to 70 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis method. Analytical size exclusion chromatography revealed an approximately sevenfold increase in apparent size of produced protein. Although the in vitro potency of the fusion protein was significantly reduced (1.26 ± 0.05 vs. 0.24 ± 0.03 ng/ml) but, the in vivo activity was considerably increased up to 1.58 × 105 IU/ml in normocythemic mice assay. Pharmacokinetic animal studies revealed strongly 15.6-fold plasma half-life extension for the PASylated EPO (83.16 ± 13.28 h) in comparison to epoetin α (8.5 ± 2.4 h) and darbepoetin α (25.3 ± 2.2h).

In silico designing of hyper-glycosylated analogs for the human coagulation factor IX.

N-glycosylation is a process during which a glycan moiety attaches to the asparagine residue in the N-glycosylation consensus sequence (Asn-Xxx-Ser/Thr), where Xxx can be any amino acid except proline. Introduction of a new N-glycosylation site into a protein backbone leads to its hyper-glycosylation, and may improve the protein properties such as solubility, folding, stability, and secretion. Glyco-engineering is an approach to facilitate the hyper-glycosylation of recombinant proteins by application of the site-directed mutagenesis methods. In this regard, selection of a suitable location on the surface of a protein for introduction of a new N-glycosylation site is a main concern. In this work, a computational approach was conducted to select suitable location(s) for introducing new N-glycosylation sites into the human coagulation factor IX (hFIX). With this aim, the first 45 residues of mature hFIX were explored to find out suitable positions for introducing either Asn or Ser/Thr residues, to create new N-glycosylation site(s). Our exploration lead to detection of five potential positions, for hyper-glycosylation. For each suggested position, an analog was defined and subjected for N-glycosylation efficiency prediction. After generation of three-dimensional structures, by homology-based modeling, the five designed analogs were examined by molecular dynamic (MD) simulations, to predict their stability levels and probable structural distortions caused by amino acid substitutions, relative to the native counterpart. Three out of five suggested analogs, namely; E15T, K22N, and R37N, reached equilibration state with relatively constant Root Mean Square Deviation values. Additional analysis on the data obtained during MD simulations, lead us to conclude that, R37N is the only qualified analog with the most similar structure and dynamic behavior to that of the native counterpart, to be considered for further experimental investigations.

uPAR peptide antagonist alters regulation of MAP kinases and Bcl-2 family members in favor of apoptosis in MDA-MB-231 cell line.

Urokinase plasminogen activator receptor (uPAR) and its ligands play a major role in many tumors by mediating extracellular matrix degradation and signaling cascades leading to tumor growth, invasion and metastasis. Recently we introduced uPAR decapeptide antagonist with cytotoxic effect on MDA-MB-231 cell line. In this study we assessed the alteration in uPAR downstream signaling following treatment with the peptide antagonist. In this regard, extracellular-signal-regulated kinase (ERK) and p38 from mitogen-activated protein kinase family and Bcl-2, Bim and Bax from Bcl-2 protein family were investigated. Our data revealed that the peptide caused p38 activation and low ERK activation. On the other hand, the peptide induced down-regulation of Bcl-2 and up-regulation of Bim without Bax modulation. Changes in target protein expression/activation explain the apoptotic property of the peptide and highlight its potential to be used as a therapeutic agent in cancerous cells expressing high levels of uPAR.

Natural suppressor cells; past, present and future.

Myeloid Derived Suppressor Cells (MDSCs) are a mixed group of bone marrow-derived myeloid cells containing macrophages, granulocytes, immature DCs and early myeloid precursors that have immune suppressive activity. MDSCs infiltrate the BM, spleen and peripheral blood of tumors-bearing experimental animals and are found in the blood of cancer patients as a result of tumor-induced alterations in myelopoiesis. Evidence from murine model systems indicated that myeloid-derived cells with suppressor activity also accumulate in non-tumor bearing hosts in response to infection, chemotherapy, stress, and immune senescence. MDSCs are considered key negative regulators of immune responses. Their association with tumor-associated immune defects make MDSCs an attractive target for therapeutic intervention in cancer.

Production and characterization of liquid-stored and lyophilized reconstituted human infusible platelet membranes.

INTRODUCTION: During recent years, the need for platelet concentrate (PC) has increased. Infusible platelet membranes (IPM) have been developed as an alternative to standard PCs, with the additional advantage of long shelf-life and increased viral safety. In this study, IPM construction and the morphological and biological features of these microvesicles were surveyed to determine their binding capacities in vitro. METHODS: Thirty-five PC units prepared by the Iranian Blood Transfusion Organization were used to produce IPM. Platelets were lysed by repeated cycles of freezing and thawing, virally inactivated with wet heat in the presence of different concentrations of sodium octanoate as a heat stabilizer, and then sonicated. IPM were separated, kept at 4°C or lyophilized, and examined for binding to collagen and von Willebrand factor (VWF). RESULTS: IPM retained the binding capacity for collagen and VWF, and the extent of VWF binding was dependent on the concentration of the heat stabilizer. Additionally, a higher binding capacity was demonstrated for liquid-stored compared with lyophilized IPM. CONCLUSION: This study revealed the potential of IPM microvesicles to mimic the binding features of platelets in vitro.

Angiotensin II induces NF-κB, JNK and p38 MAPK activation in monocytic cells and increases matrix metalloproteinase-9 expression in a PKC- andRho kinase-dependent manner

Angiotensin II (ANG II), the main effector of the renin-angiotensin system, is implicated in endothelial permeability, recruitment and activation of the immune cells, and also vascular remodeling through induction of inflammatory genes. Matrix metalloproteinases (MMPs) are considered to be important inflammatory factors. Elucidation of ANG II signaling pathways and of possible cross-talks between their components is essential for the development of efficient inhibitory medications. The current study investigates the inflammatory signaling pathways activated by ANG II in cultures of human monocytic U-937 cells, and the effects of specific pharmacological inhibitors of signaling intermediates on MMP-9 gene (MMP-9) expression and activity. MMP-9 expression was determined by real-time PCR and supernatants were analyzed for MMP-9 activity by ELISA and zymography methods. A multi-target ELISA kit was employed to evaluate IκB, NF-κB, JNK, p38, and STAT3 activation following treatments. Stimulation with ANG II (100 nM) significantly increased MMP-9 expression and activity, and also activated NF-κB, JNK, and p38 by 3.8-, 2.8- and 2.2-fold, respectively (P < 0.01). ANG II-induced MMP-9 expression was significantly reduced by 75 and 67 percent, respectively, by co-incubation of the cells with a selective inhibitor of protein kinase C (GF109203X, 5 µM) or of rho kinase (Y-27632, 15 µM), but not with inhibitors of phosphoinositide 3-kinase (wortmannin, 200 nM), tyrosine kinases (genistein, 100 µM) or of reactive oxygen species (α-tocopherol, 100 µM). Thus, protein kinase C and Rho kinase are important components of the inflammatory signaling pathways activated by ANG II to increase MMP-9 expression in monocytic cells. Both signaling molecules may constitute potential targets for effective management of inflammation.

Angiotensin II induces NF-κB, JNK and p38 MAPK activation in monocytic cells and increases matrix metalloproteinase-9 expression in a PKC- andRho kinase-dependent manner.

Angiotensin II (ANG II), the main effector of the renin-angiotensin system, is implicated in endothelial permeability, recruitment and activation of the immune cells, and also vascular remodeling through induction of inflammatory genes. Matrix metalloproteinases (MMPs) are considered to be important inflammatory factors. Elucidation of ANG II signaling pathways and of possible cross-talks between their components is essential for the development of efficient inhibitory medications. The current study investigates the inflammatory signaling pathways activated by ANG II in cultures of human monocytic U-937 cells, and the effects of specific pharmacological inhibitors of signaling intermediates on MMP-9 gene (MMP-9) expression and activity. MMP-9 expression was determined by real-time PCR and supernatants were analyzed for MMP-9 activity by ELISA and zymography methods. A multi-target ELISA kit was employed to evaluate IκB, NF-κB, JNK, p38, and STAT3 activation following treatments. Stimulation with ANG II (100 nM) significantly increased MMP-9 expression and activity, and also activated NF-κB, JNK, and p38 by 3.8-, 2.8- and 2.2-fold, respectively (P < 0.01). ANG II-induced MMP-9 expression was significantly reduced by 75 and 67%, respectively, by co-incubation of the cells with a selective inhibitor of protein kinase C (GF109203X, 5 µM) or of rho kinase (Y-27632, 15 µM), but not with inhibitors of phosphoinositide 3-kinase (wortmannin, 200 nM), tyrosine kinases (genistein, 100 µM) or of reactive oxygen species (α-tocopherol, 100 µM). Thus, protein kinase C and Rho kinase are important components of the inflammatory signaling pathways activated by ANG II to increase MMP-9 expression in monocytic cells. Both signaling molecules may constitute potential targets for effective management of inflammation.

The prevalence of cagA and cagE genes in Helicobacter pylori strains isolated from different patient groups by polymerase chain reaction.

The aim of this study was to investigate the prevalence of cagA and cagE genes in H. pylori strains isolated from different patient groups with Non-Ulcer Dyspepsia (NUD), Duodenal Ulcer (DU), Gastric Ulcer (GU) and Gastric Cancer (GC). The patients admitted to the gastroenterology unit at Sharyati hospital in Tehran in 2006 were included in this study. Gastric biopsy specimens were obtained from the antrum of the stomach from each patient then cultured for detection of H. pylori. Identification of H. pylori was performed according to the standard bacteriological methods. Genomic DNA was extracted using a commercially available Qia gene kit. PCR was done using primers cagA-F, cagA-R and cagE-F, cagE-R to detect the target genes cagA and cagE, respectively. Amplified products of target genes were confirmed by sequencing. The cagA and cagE were detected among 85 and 86% of H. pylori isolates, respectively. Prevalence of cagA and cagE genes in the patients with NUD, DU, GU and GC were 22 (64.7%), 28 (100%), 18 (90%), 10 (100%) and 25 (73.5%), 27 (96.4%), 19 (95%), 7 (70%), respectively. The current study demonstrated a significant correlation between peptic ulceration and the presence of H. pylori isolates carrying cagE and cagA genes in Iranian patients.

Two matrix metalloproteinases inhibitors from Ferula persica var. persica.

Matrix metalloproteinases (MMPs) play a role in several physiologic and pathologic events. There is some evidence indicating the involvement of MMPs in tumor invasion and inflammatory diseases. Here we studied the chloroform extract of Ferula persica var. persica. The influence of these extracts vs. a reference drug, diclofenac sodium, on MMP production by the fibrosarcoma cell line was investigated using an in vitro cytotoxicity assay, sodium dodecyl sulfate-polyacrylamide, and gelatin zymography. The total extract of the roots was found to exhibit a selective inhibitory effect on tumor cell invasion. The bioactivity-guided fractionation of this extract led to the isolation of two compounds. These compounds showed highest MMP inhibitory effect at minimal toxic dose levels. Using conventional spectroscopy methods, the active fractions were identified as t-butyl 3-[(1-methylthiopropyl)dithio]-2-propenyl malonate (persicasulphide B) and umbelliprenin, previously isolated from F. persica var. latisecta. Since inhibition of MMP activity has been employed in modality therapy in diseases such as cancer, this compound might be promising in the preparation of anti-MMP therapeutic derivatives.

Occurrence of enteropathogenic bacteria in children under 5 years with diarrhoea in south Tehran.

This study was carried out on 1600 rectal swabs from children under 5 years of age admitted at the health centre in Islamshahr, Tehran province, Islamic Republic of Iran, during 1998-99. The specimens were examined for various bacterial pathogens. Isolation rates were: enteropathogenic Escherichia coli 6.8%, Shigella spp. 3.4%, Salmonella spp. 2.9%, Campylobacter spp. 0.9%, Yersinia spp. 0.7%. The isolation rate was highest in the summer, except for Yersinia spp., which was predominantly isolated in spring. The results of this study demonstrate the significance of Yersinia spp. and Campylobacter spp. in patients with diarrhoea.

Occurrence of enteropathogenic bacteria in children under 5 years with diarrhoea in south Tehran

This study was carried out on 1600 rectal swabs from children under 5 years of age admitted at the health centre in Islamshahr, Tehran province, Islamic Republic of Iran, during 1998-99. The specimens were examined for various bacterial pathogens. Isolation rates were: enteropathogenic Escherichia coli 6.8%, Shigella spp. 3.4%, Salmonella spp. 2.9%, Campylobacter spp. 0.9%, Yersinia spp. 0.7%. The isolation rate was highest in the summer, except for Yersinia spp., which was predominantly isolated in spring. The results of this study demonstrate the significance of Yersinia spp. And Campylobacter spp. in patients with diarrhoea

Sodium alginate as a novel therapeutic option in experimental colitis.

The potential therapeutic effect of low-viscosity sodium alginate (LVA) was studied in a rat model of acute colitis induced by intracolonic administration of acetic acid. This experimental model produced a significant ulcerative colitis. Induction of colitis also significantly enhanced the serum and colonic mucosal cytokine (IL-6 and TNF-alpha) and eicosanoid (LTB4 and PGE2) levels, which paralleled with the severity of colitis. LVA solution was administered orally as drinking water at concentration of 0.5% (W/V) for 1 week. The tolerability and inhibitory effect of LVA on matrix metalloproteinase-2 (MMP-2) were tested using WEHI-164 cell line and zymography method. The results showed that LVA therapy is able to significantly reduce colonic damage score, histological lesion, serum and colonic mucosal IL-6, TNF-alpha, LTB4 and PGE2 levels in treated group compared with nontreated controls. Moreover, in vitro examinations revealed that treatment with LVA could diminish MMP-2 activity. It is concluded that LVA is able to suppress acetic acid-induced colitis in rats. Some of the action of LVA may be associated with its inhibitory effects on cytokine and eicosanoid production and MMP-2 activity. Our data suggest that LVA could potentially be a novel therapeutic option for inflammatory bowel disease.

Effect of piroxicam on matrix metalloproteinase 2 and apoptosis.

We examined the effect of a nonsteroidal anti-inflammatory drug (NSAID), piroxicam, on apoptosis and matrix metalloproteinase 2 (MMP-2) activity compared with diclofenac and dexamethasone. The fibrosarcoma (WEHI-164) cell line was used to assess tolerability, MMP-2 activity and apoptosis. Piroxicam, dexamethasone and diclofenac were used at concentrations of 10-200 microg/ml in triplicate and 2-fold dilutions. MMP-2 activity was assessed using zymography. For assessment of apoptosis, the terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) method was used. The results of this study show that piroxicam is able to diminish MMP-2 activity and induce apoptosis under in vitro conditions. Piroxicam also showed high tolerability compared with diclofenac and dexamethasone. In conclusion, piroxicam is able to induce apoptosis and suppress MMP-2 activity.